561671 has 4 divisors (see below), whose sum is σ = 612744. Its totient is φ = 510600.

The previous prime is 561667. The next prime is 561703. The reversal of 561671 is 176165.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 561671 - 2² = 561667 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 561671.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (564671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25520 + ... + 25541.

It is an arithmetic number, because the mean of its divisors is an integer number (153186).

2⁵⁶¹⁶⁷¹ is an apocalyptic number.

561671 is a deficient number, since it is larger than the sum of its proper divisors (51073).

561671 is a wasteful number, since it uses less digits than its factorization.

561671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51072.

The product of its digits is 1260, while the sum is 26.

The square root of 561671 is about 749.4471295562. The cubic root of 561671 is about 82.5076087259.

The spelling of 561671 in words is "five hundred sixty-one thousand, six hundred seventy-one".